/*-
 * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
 *
 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Voltaire, Inc.  All rights reserved.
 * Copyright (c) 2006 Intel Corporation.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <sys/cdefs.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/random.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/kref.h>
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/etherdevice.h>
#include <rdma/ib_pack.h>
#include <rdma/ib_cache.h>
#include <rdma/ib_user_sa.h>
#include <rdma/ib_marshall.h>
#include <rdma/ib_addr.h>
#include "sa.h"
#include "core_priv.h"

#define IB_SA_LOCAL_SVC_TIMEOUT_MIN             100
#define IB_SA_LOCAL_SVC_TIMEOUT_DEFAULT         2000
#define IB_SA_LOCAL_SVC_TIMEOUT_MAX             200000

struct ib_sa_sm_ah {
        struct ib_ah        *ah;
        struct kref          ref;
        u16                  pkey_index;
        u8                   src_path_mask;
};

struct ib_sa_classport_cache {
        bool valid;
        struct ib_class_port_info data;
};

struct ib_sa_port {
        struct ib_mad_agent *agent;
        struct ib_sa_sm_ah  *sm_ah;
        struct work_struct   update_task;
        struct ib_sa_classport_cache classport_info;
        spinlock_t                   classport_lock; /* protects class port info set */
        spinlock_t           ah_lock;
        u8                   port_num;
};

struct ib_sa_device {
        int                     start_port, end_port;
        struct ib_event_handler event_handler;
        struct ib_sa_port port[0];
};

struct ib_sa_query {
        void (*callback)(struct ib_sa_query *, int, struct ib_sa_mad *);
        void (*release)(struct ib_sa_query *);
        struct ib_sa_client    *client;
        struct ib_sa_port      *port;
        struct ib_mad_send_buf *mad_buf;
        struct ib_sa_sm_ah     *sm_ah;
        int                     id;
        u32                     flags;
        struct list_head        list; /* Local svc request list */
        u32                     seq; /* Local svc request sequence number */
        unsigned long           timeout; /* Local svc timeout */
        u8                      path_use; /* How will the pathrecord be used */
};

#define IB_SA_ENABLE_LOCAL_SERVICE      0x00000001
#define IB_SA_CANCEL                    0x00000002

struct ib_sa_service_query {
        void (*callback)(int, struct ib_sa_service_rec *, void *);
        void *context;
        struct ib_sa_query sa_query;
};

struct ib_sa_path_query {
        void (*callback)(int, struct ib_sa_path_rec *, void *);
        void *context;
        struct ib_sa_query sa_query;
};

struct ib_sa_guidinfo_query {
        void (*callback)(int, struct ib_sa_guidinfo_rec *, void *);
        void *context;
        struct ib_sa_query sa_query;
};

struct ib_sa_classport_info_query {
        void (*callback)(int, struct ib_class_port_info *, void *);
        void *context;
        struct ib_sa_query sa_query;
};

struct ib_sa_mcmember_query {
        void (*callback)(int, struct ib_sa_mcmember_rec *, void *);
        void *context;
        struct ib_sa_query sa_query;
};

static void ib_sa_add_one(struct ib_device *device);
static void ib_sa_remove_one(struct ib_device *device, void *client_data);

static struct ib_client sa_client = {
        .name   = "sa",
        .add    = ib_sa_add_one,
        .remove = ib_sa_remove_one
};

static DEFINE_SPINLOCK(idr_lock);
static DEFINE_IDR(query_idr);

static DEFINE_SPINLOCK(tid_lock);
static u32 tid;

#define PATH_REC_FIELD(field) \
        .struct_offset_bytes = offsetof(struct ib_sa_path_rec, field),          \
        .struct_size_bytes   = sizeof ((struct ib_sa_path_rec *) 0)->field,     \
        .field_name          = "sa_path_rec:" #field

static const struct ib_field path_rec_table[] = {
        { PATH_REC_FIELD(service_id),
          .offset_words = 0,
          .offset_bits  = 0,
          .size_bits    = 64 },
        { PATH_REC_FIELD(dgid),
          .offset_words = 2,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { PATH_REC_FIELD(sgid),
          .offset_words = 6,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { PATH_REC_FIELD(dlid),
          .offset_words = 10,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { PATH_REC_FIELD(slid),
          .offset_words = 10,
          .offset_bits  = 16,
          .size_bits    = 16 },
        { PATH_REC_FIELD(raw_traffic),
          .offset_words = 11,
          .offset_bits  = 0,
          .size_bits    = 1 },
        { RESERVED,
          .offset_words = 11,
          .offset_bits  = 1,
          .size_bits    = 3 },
        { PATH_REC_FIELD(flow_label),
          .offset_words = 11,
          .offset_bits  = 4,
          .size_bits    = 20 },
        { PATH_REC_FIELD(hop_limit),
          .offset_words = 11,
          .offset_bits  = 24,
          .size_bits    = 8 },
        { PATH_REC_FIELD(traffic_class),
          .offset_words = 12,
          .offset_bits  = 0,
          .size_bits    = 8 },
        { PATH_REC_FIELD(reversible),
          .offset_words = 12,
          .offset_bits  = 8,
          .size_bits    = 1 },
        { PATH_REC_FIELD(numb_path),
          .offset_words = 12,
          .offset_bits  = 9,
          .size_bits    = 7 },
        { PATH_REC_FIELD(pkey),
          .offset_words = 12,
          .offset_bits  = 16,
          .size_bits    = 16 },
        { PATH_REC_FIELD(qos_class),
          .offset_words = 13,
          .offset_bits  = 0,
          .size_bits    = 12 },
        { PATH_REC_FIELD(sl),
          .offset_words = 13,
          .offset_bits  = 12,
          .size_bits    = 4 },
        { PATH_REC_FIELD(mtu_selector),
          .offset_words = 13,
          .offset_bits  = 16,
          .size_bits    = 2 },
        { PATH_REC_FIELD(mtu),
          .offset_words = 13,
          .offset_bits  = 18,
          .size_bits    = 6 },
        { PATH_REC_FIELD(rate_selector),
          .offset_words = 13,
          .offset_bits  = 24,
          .size_bits    = 2 },
        { PATH_REC_FIELD(rate),
          .offset_words = 13,
          .offset_bits  = 26,
          .size_bits    = 6 },
        { PATH_REC_FIELD(packet_life_time_selector),
          .offset_words = 14,
          .offset_bits  = 0,
          .size_bits    = 2 },
        { PATH_REC_FIELD(packet_life_time),
          .offset_words = 14,
          .offset_bits  = 2,
          .size_bits    = 6 },
        { PATH_REC_FIELD(preference),
          .offset_words = 14,
          .offset_bits  = 8,
          .size_bits    = 8 },
        { RESERVED,
          .offset_words = 14,
          .offset_bits  = 16,
          .size_bits    = 48 },
};

#define MCMEMBER_REC_FIELD(field) \
        .struct_offset_bytes = offsetof(struct ib_sa_mcmember_rec, field),      \
        .struct_size_bytes   = sizeof ((struct ib_sa_mcmember_rec *) 0)->field, \
        .field_name          = "sa_mcmember_rec:" #field

static const struct ib_field mcmember_rec_table[] = {
        { MCMEMBER_REC_FIELD(mgid),
          .offset_words = 0,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { MCMEMBER_REC_FIELD(port_gid),
          .offset_words = 4,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { MCMEMBER_REC_FIELD(qkey),
          .offset_words = 8,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { MCMEMBER_REC_FIELD(mlid),
          .offset_words = 9,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { MCMEMBER_REC_FIELD(mtu_selector),
          .offset_words = 9,
          .offset_bits  = 16,
          .size_bits    = 2 },
        { MCMEMBER_REC_FIELD(mtu),
          .offset_words = 9,
          .offset_bits  = 18,
          .size_bits    = 6 },
        { MCMEMBER_REC_FIELD(traffic_class),
          .offset_words = 9,
          .offset_bits  = 24,
          .size_bits    = 8 },
        { MCMEMBER_REC_FIELD(pkey),
          .offset_words = 10,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { MCMEMBER_REC_FIELD(rate_selector),
          .offset_words = 10,
          .offset_bits  = 16,
          .size_bits    = 2 },
        { MCMEMBER_REC_FIELD(rate),
          .offset_words = 10,
          .offset_bits  = 18,
          .size_bits    = 6 },
        { MCMEMBER_REC_FIELD(packet_life_time_selector),
          .offset_words = 10,
          .offset_bits  = 24,
          .size_bits    = 2 },
        { MCMEMBER_REC_FIELD(packet_life_time),
          .offset_words = 10,
          .offset_bits  = 26,
          .size_bits    = 6 },
        { MCMEMBER_REC_FIELD(sl),
          .offset_words = 11,
          .offset_bits  = 0,
          .size_bits    = 4 },
        { MCMEMBER_REC_FIELD(flow_label),
          .offset_words = 11,
          .offset_bits  = 4,
          .size_bits    = 20 },
        { MCMEMBER_REC_FIELD(hop_limit),
          .offset_words = 11,
          .offset_bits  = 24,
          .size_bits    = 8 },
        { MCMEMBER_REC_FIELD(scope),
          .offset_words = 12,
          .offset_bits  = 0,
          .size_bits    = 4 },
        { MCMEMBER_REC_FIELD(join_state),
          .offset_words = 12,
          .offset_bits  = 4,
          .size_bits    = 4 },
        { MCMEMBER_REC_FIELD(proxy_join),
          .offset_words = 12,
          .offset_bits  = 8,
          .size_bits    = 1 },
        { RESERVED,
          .offset_words = 12,
          .offset_bits  = 9,
          .size_bits    = 23 },
};

#define SERVICE_REC_FIELD(field) \
        .struct_offset_bytes = offsetof(struct ib_sa_service_rec, field),       \
        .struct_size_bytes   = sizeof ((struct ib_sa_service_rec *) 0)->field,  \
        .field_name          = "sa_service_rec:" #field

static const struct ib_field service_rec_table[] = {
        { SERVICE_REC_FIELD(id),
          .offset_words = 0,
          .offset_bits  = 0,
          .size_bits    = 64 },
        { SERVICE_REC_FIELD(gid),
          .offset_words = 2,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { SERVICE_REC_FIELD(pkey),
          .offset_words = 6,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { SERVICE_REC_FIELD(lease),
          .offset_words = 7,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { SERVICE_REC_FIELD(key),
          .offset_words = 8,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { SERVICE_REC_FIELD(name),
          .offset_words = 12,
          .offset_bits  = 0,
          .size_bits    = 64*8 },
        { SERVICE_REC_FIELD(data8),
          .offset_words = 28,
          .offset_bits  = 0,
          .size_bits    = 16*8 },
        { SERVICE_REC_FIELD(data16),
          .offset_words = 32,
          .offset_bits  = 0,
          .size_bits    = 8*16 },
        { SERVICE_REC_FIELD(data32),
          .offset_words = 36,
          .offset_bits  = 0,
          .size_bits    = 4*32 },
        { SERVICE_REC_FIELD(data64),
          .offset_words = 40,
          .offset_bits  = 0,
          .size_bits    = 2*64 },
};

#define CLASSPORTINFO_REC_FIELD(field) \
        .struct_offset_bytes = offsetof(struct ib_class_port_info, field),      \
        .struct_size_bytes   = sizeof((struct ib_class_port_info *)0)->field,   \
        .field_name          = "ib_class_port_info:" #field

static const struct ib_field classport_info_rec_table[] = {
        { CLASSPORTINFO_REC_FIELD(base_version),
          .offset_words = 0,
          .offset_bits  = 0,
          .size_bits    = 8 },
        { CLASSPORTINFO_REC_FIELD(class_version),
          .offset_words = 0,
          .offset_bits  = 8,
          .size_bits    = 8 },
        { CLASSPORTINFO_REC_FIELD(capability_mask),
          .offset_words = 0,
          .offset_bits  = 16,
          .size_bits    = 16 },
        { CLASSPORTINFO_REC_FIELD(cap_mask2_resp_time),
          .offset_words = 1,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { CLASSPORTINFO_REC_FIELD(redirect_gid),
          .offset_words = 2,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { CLASSPORTINFO_REC_FIELD(redirect_tcslfl),
          .offset_words = 6,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { CLASSPORTINFO_REC_FIELD(redirect_lid),
          .offset_words = 7,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { CLASSPORTINFO_REC_FIELD(redirect_pkey),
          .offset_words = 7,
          .offset_bits  = 16,
          .size_bits    = 16 },

        { CLASSPORTINFO_REC_FIELD(redirect_qp),
          .offset_words = 8,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { CLASSPORTINFO_REC_FIELD(redirect_qkey),
          .offset_words = 9,
          .offset_bits  = 0,
          .size_bits    = 32 },

        { CLASSPORTINFO_REC_FIELD(trap_gid),
          .offset_words = 10,
          .offset_bits  = 0,
          .size_bits    = 128 },
        { CLASSPORTINFO_REC_FIELD(trap_tcslfl),
          .offset_words = 14,
          .offset_bits  = 0,
          .size_bits    = 32 },

        { CLASSPORTINFO_REC_FIELD(trap_lid),
          .offset_words = 15,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { CLASSPORTINFO_REC_FIELD(trap_pkey),
          .offset_words = 15,
          .offset_bits  = 16,
          .size_bits    = 16 },

        { CLASSPORTINFO_REC_FIELD(trap_hlqp),
          .offset_words = 16,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { CLASSPORTINFO_REC_FIELD(trap_qkey),
          .offset_words = 17,
          .offset_bits  = 0,
          .size_bits    = 32 },
};

#define GUIDINFO_REC_FIELD(field) \
        .struct_offset_bytes = offsetof(struct ib_sa_guidinfo_rec, field),      \
        .struct_size_bytes   = sizeof((struct ib_sa_guidinfo_rec *) 0)->field,  \
        .field_name          = "sa_guidinfo_rec:" #field

static const struct ib_field guidinfo_rec_table[] = {
        { GUIDINFO_REC_FIELD(lid),
          .offset_words = 0,
          .offset_bits  = 0,
          .size_bits    = 16 },
        { GUIDINFO_REC_FIELD(block_num),
          .offset_words = 0,
          .offset_bits  = 16,
          .size_bits    = 8 },
        { GUIDINFO_REC_FIELD(res1),
          .offset_words = 0,
          .offset_bits  = 24,
          .size_bits    = 8 },
        { GUIDINFO_REC_FIELD(res2),
          .offset_words = 1,
          .offset_bits  = 0,
          .size_bits    = 32 },
        { GUIDINFO_REC_FIELD(guid_info_list),
          .offset_words = 2,
          .offset_bits  = 0,
          .size_bits    = 512 },
};

static inline void ib_sa_disable_local_svc(struct ib_sa_query *query)
{
        query->flags &= ~IB_SA_ENABLE_LOCAL_SERVICE;
}

static void free_sm_ah(struct kref *kref)
{
        struct ib_sa_sm_ah *sm_ah = container_of(kref, struct ib_sa_sm_ah, ref);

        ib_destroy_ah(sm_ah->ah, 0);
        kfree(sm_ah);
}

static void update_sm_ah(struct work_struct *work)
{
        struct ib_sa_port *port =
                container_of(work, struct ib_sa_port, update_task);
        struct ib_sa_sm_ah *new_ah;
        struct ib_port_attr port_attr;
        struct ib_ah_attr   ah_attr;

        if (ib_query_port(port->agent->device, port->port_num, &port_attr)) {
                pr_warn("Couldn't query port\n");
                return;
        }

        new_ah = kmalloc(sizeof *new_ah, GFP_KERNEL);
        if (!new_ah) {
                return;
        }

        kref_init(&new_ah->ref);
        new_ah->src_path_mask = (1 << port_attr.lmc) - 1;

        new_ah->pkey_index = 0;
        if (ib_find_pkey(port->agent->device, port->port_num,
                         IB_DEFAULT_PKEY_FULL, &new_ah->pkey_index))
                pr_err("Couldn't find index for default PKey\n");

        memset(&ah_attr, 0, sizeof ah_attr);
        ah_attr.dlid     = port_attr.sm_lid;
        ah_attr.sl       = port_attr.sm_sl;
        ah_attr.port_num = port->port_num;
        if (port_attr.grh_required) {
                ah_attr.ah_flags = IB_AH_GRH;
                ah_attr.grh.dgid.global.subnet_prefix = cpu_to_be64(port_attr.subnet_prefix);
                ah_attr.grh.dgid.global.interface_id = cpu_to_be64(IB_SA_WELL_KNOWN_GUID);
        }

        new_ah->ah = ib_create_ah(port->agent->qp->pd, &ah_attr, RDMA_CREATE_AH_SLEEPABLE);
        if (IS_ERR(new_ah->ah)) {
                pr_warn("Couldn't create new SM AH\n");
                kfree(new_ah);
                return;
        }

        spin_lock_irq(&port->ah_lock);
        if (port->sm_ah)
                kref_put(&port->sm_ah->ref, free_sm_ah);
        port->sm_ah = new_ah;
        spin_unlock_irq(&port->ah_lock);

}

static void ib_sa_event(struct ib_event_handler *handler, struct ib_event *event)
{
        if (event->event == IB_EVENT_PORT_ERR    ||
            event->event == IB_EVENT_PORT_ACTIVE ||
            event->event == IB_EVENT_LID_CHANGE  ||
            event->event == IB_EVENT_PKEY_CHANGE ||
            event->event == IB_EVENT_SM_CHANGE   ||
            event->event == IB_EVENT_CLIENT_REREGISTER) {
                unsigned long flags;
                struct ib_sa_device *sa_dev =
                        container_of(handler, typeof(*sa_dev), event_handler);
                struct ib_sa_port *port =
                        &sa_dev->port[event->element.port_num - sa_dev->start_port];

                if (!rdma_cap_ib_sa(handler->device, port->port_num))
                        return;

                spin_lock_irqsave(&port->ah_lock, flags);
                if (port->sm_ah)
                        kref_put(&port->sm_ah->ref, free_sm_ah);
                port->sm_ah = NULL;
                spin_unlock_irqrestore(&port->ah_lock, flags);

                if (event->event == IB_EVENT_SM_CHANGE ||
                    event->event == IB_EVENT_CLIENT_REREGISTER ||
                    event->event == IB_EVENT_LID_CHANGE) {
                        spin_lock_irqsave(&port->classport_lock, flags);
                        port->classport_info.valid = false;
                        spin_unlock_irqrestore(&port->classport_lock, flags);
                }
                queue_work(ib_wq, &sa_dev->port[event->element.port_num -
                                            sa_dev->start_port].update_task);
        }
}

void ib_sa_register_client(struct ib_sa_client *client)
{
        atomic_set(&client->users, 1);
        init_completion(&client->comp);
}
EXPORT_SYMBOL(ib_sa_register_client);

void ib_sa_unregister_client(struct ib_sa_client *client)
{
        ib_sa_client_put(client);
        wait_for_completion(&client->comp);
}
EXPORT_SYMBOL(ib_sa_unregister_client);

/**
 * ib_sa_cancel_query - try to cancel an SA query
 * @id:ID of query to cancel
 * @query:query pointer to cancel
 *
 * Try to cancel an SA query.  If the id and query don't match up or
 * the query has already completed, nothing is done.  Otherwise the
 * query is canceled and will complete with a status of -EINTR.
 */
void ib_sa_cancel_query(int id, struct ib_sa_query *query)
{
        unsigned long flags;
        struct ib_mad_agent *agent;
        struct ib_mad_send_buf *mad_buf;

        spin_lock_irqsave(&idr_lock, flags);
        if (idr_find(&query_idr, id) != query) {
                spin_unlock_irqrestore(&idr_lock, flags);
                return;
        }
        agent = query->port->agent;
        mad_buf = query->mad_buf;
        spin_unlock_irqrestore(&idr_lock, flags);

        ib_cancel_mad(agent, mad_buf);
}
EXPORT_SYMBOL(ib_sa_cancel_query);

static u8 get_src_path_mask(struct ib_device *device, u8 port_num)
{
        struct ib_sa_device *sa_dev;
        struct ib_sa_port   *port;
        unsigned long flags;
        u8 src_path_mask;

        sa_dev = ib_get_client_data(device, &sa_client);
        if (!sa_dev)
                return 0x7f;

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        spin_lock_irqsave(&port->ah_lock, flags);
        src_path_mask = port->sm_ah ? port->sm_ah->src_path_mask : 0x7f;
        spin_unlock_irqrestore(&port->ah_lock, flags);

        return src_path_mask;
}

int ib_init_ah_from_path(struct ib_device *device, u8 port_num,
                         struct ib_sa_path_rec *rec, struct ib_ah_attr *ah_attr)
{
        int ret;
        u16 gid_index;
        int use_roce;
        if_t ndev = NULL;

        memset(ah_attr, 0, sizeof *ah_attr);
        ah_attr->dlid = be16_to_cpu(rec->dlid);
        ah_attr->sl = rec->sl;
        ah_attr->src_path_bits = be16_to_cpu(rec->slid) &
                                 get_src_path_mask(device, port_num);
        ah_attr->port_num = port_num;
        ah_attr->static_rate = rec->rate;

        use_roce = rdma_cap_eth_ah(device, port_num);

        if (use_roce) {
                if_t idev;
                if_t resolved_dev;
                struct rdma_dev_addr dev_addr = {.bound_dev_if = rec->ifindex,
                                                 .net = rec->net ? rec->net :
                                                         &init_net};
                union rdma_sockaddr sgid_addr, dgid_addr;

                if (!device->get_netdev)
                        return -EOPNOTSUPP;

                rdma_gid2ip(&sgid_addr._sockaddr, &rec->sgid);
                rdma_gid2ip(&dgid_addr._sockaddr, &rec->dgid);

                /* validate the route */
                ret = rdma_resolve_ip_route(&sgid_addr._sockaddr,
                                            &dgid_addr._sockaddr, &dev_addr);
                if (ret)
                        return ret;

                if ((dev_addr.network == RDMA_NETWORK_IPV4 ||
                     dev_addr.network == RDMA_NETWORK_IPV6) &&
                    rec->gid_type != IB_GID_TYPE_ROCE_UDP_ENCAP)
                        return -EINVAL;

                idev = device->get_netdev(device, port_num);
                if (!idev)
                        return -ENODEV;

                resolved_dev = dev_get_by_index(dev_addr.net,
                                                dev_addr.bound_dev_if);
                if (!resolved_dev) {
                        dev_put(idev);
                        return -ENODEV;
                }
                ndev = ib_get_ndev_from_path(rec);
                if ((ndev && ndev != resolved_dev) ||
                    (resolved_dev != idev &&
                     rdma_vlan_dev_real_dev(resolved_dev) != idev))
                        ret = -EHOSTUNREACH;
                dev_put(idev);
                dev_put(resolved_dev);
                if (ret) {
                        if (ndev)
                                dev_put(ndev);
                        return ret;
                }
        }

        if (rec->hop_limit > 0 || use_roce) {
                ah_attr->ah_flags = IB_AH_GRH;
                ah_attr->grh.dgid = rec->dgid;

                ret = ib_find_cached_gid_by_port(device, &rec->sgid,
                                                 rec->gid_type, port_num, ndev,
                                                 &gid_index);
                if (ret) {
                        if (ndev)
                                dev_put(ndev);
                        return ret;
                }

                ah_attr->grh.sgid_index    = gid_index;
                ah_attr->grh.flow_label    = be32_to_cpu(rec->flow_label);
                ah_attr->grh.hop_limit     = rec->hop_limit;
                ah_attr->grh.traffic_class = rec->traffic_class;
                if (ndev)
                        dev_put(ndev);
        }

        if (use_roce)
                memcpy(ah_attr->dmac, rec->dmac, ETH_ALEN);

        return 0;
}
EXPORT_SYMBOL(ib_init_ah_from_path);

static int alloc_mad(struct ib_sa_query *query, gfp_t gfp_mask)
{
        unsigned long flags;

        spin_lock_irqsave(&query->port->ah_lock, flags);
        if (!query->port->sm_ah) {
                spin_unlock_irqrestore(&query->port->ah_lock, flags);
                return -EAGAIN;
        }
        kref_get(&query->port->sm_ah->ref);
        query->sm_ah = query->port->sm_ah;
        spin_unlock_irqrestore(&query->port->ah_lock, flags);

        query->mad_buf = ib_create_send_mad(query->port->agent, 1,
                                            query->sm_ah->pkey_index,
                                            0, IB_MGMT_SA_HDR, IB_MGMT_SA_DATA,
                                            gfp_mask,
                                            IB_MGMT_BASE_VERSION);
        if (IS_ERR(query->mad_buf)) {
                kref_put(&query->sm_ah->ref, free_sm_ah);
                return -ENOMEM;
        }

        query->mad_buf->ah = query->sm_ah->ah;

        return 0;
}

static void free_mad(struct ib_sa_query *query)
{
        ib_free_send_mad(query->mad_buf);
        kref_put(&query->sm_ah->ref, free_sm_ah);
}

static void init_mad(struct ib_sa_mad *mad, struct ib_mad_agent *agent)
{
        unsigned long flags;

        memset(mad, 0, sizeof *mad);

        mad->mad_hdr.base_version  = IB_MGMT_BASE_VERSION;
        mad->mad_hdr.mgmt_class    = IB_MGMT_CLASS_SUBN_ADM;
        mad->mad_hdr.class_version = IB_SA_CLASS_VERSION;

        spin_lock_irqsave(&tid_lock, flags);
        mad->mad_hdr.tid           =
                cpu_to_be64(((u64) agent->hi_tid) << 32 | tid++);
        spin_unlock_irqrestore(&tid_lock, flags);
}

static int send_mad(struct ib_sa_query *query, int timeout_ms, gfp_t gfp_mask)
{
        bool preload = gfpflags_allow_blocking(gfp_mask);
        unsigned long flags;
        int ret, id;

        if (preload)
                idr_preload(gfp_mask);
        spin_lock_irqsave(&idr_lock, flags);

        id = idr_alloc(&query_idr, query, 0, 0, GFP_NOWAIT);

        spin_unlock_irqrestore(&idr_lock, flags);
        if (preload)
                idr_preload_end();
        if (id < 0)
                return id;

        query->mad_buf->timeout_ms  = timeout_ms;
        query->mad_buf->context[0] = query;
        query->id = id;

        if (query->flags & IB_SA_ENABLE_LOCAL_SERVICE) {
                ib_sa_disable_local_svc(query);
        }

        ret = ib_post_send_mad(query->mad_buf, NULL);
        if (ret) {
                spin_lock_irqsave(&idr_lock, flags);
                idr_remove(&query_idr, id);
                spin_unlock_irqrestore(&idr_lock, flags);
        }

        /*
         * It's not safe to dereference query any more, because the
         * send may already have completed and freed the query in
         * another context.
         */
        return ret ? ret : id;
}

void ib_sa_unpack_path(void *attribute, struct ib_sa_path_rec *rec)
{
        ib_unpack(path_rec_table, ARRAY_SIZE(path_rec_table), attribute, rec);
}
EXPORT_SYMBOL(ib_sa_unpack_path);

void ib_sa_pack_path(struct ib_sa_path_rec *rec, void *attribute)
{
        ib_pack(path_rec_table, ARRAY_SIZE(path_rec_table), rec, attribute);
}
EXPORT_SYMBOL(ib_sa_pack_path);

static void ib_sa_path_rec_callback(struct ib_sa_query *sa_query,
                                    int status,
                                    struct ib_sa_mad *mad)
{
        struct ib_sa_path_query *query =
                container_of(sa_query, struct ib_sa_path_query, sa_query);

        if (mad) {
                struct ib_sa_path_rec rec;

                ib_unpack(path_rec_table, ARRAY_SIZE(path_rec_table),
                          mad->data, &rec);
                rec.net = NULL;
                rec.ifindex = 0;
                rec.gid_type = IB_GID_TYPE_IB;
                eth_zero_addr(rec.dmac);
                query->callback(status, &rec, query->context);
        } else
                query->callback(status, NULL, query->context);
}

static void ib_sa_path_rec_release(struct ib_sa_query *sa_query)
{
        kfree(container_of(sa_query, struct ib_sa_path_query, sa_query));
}

/**
 * ib_sa_path_rec_get - Start a Path get query
 * @client:SA client
 * @device:device to send query on
 * @port_num: port number to send query on
 * @rec:Path Record to send in query
 * @comp_mask:component mask to send in query
 * @timeout_ms:time to wait for response
 * @gfp_mask:GFP mask to use for internal allocations
 * @callback:function called when query completes, times out or is
 * canceled
 * @context:opaque user context passed to callback
 * @sa_query:query context, used to cancel query
 *
 * Send a Path Record Get query to the SA to look up a path.  The
 * callback function will be called when the query completes (or
 * fails); status is 0 for a successful response, -EINTR if the query
 * is canceled, -ETIMEDOUT is the query timed out, or -EIO if an error
 * occurred sending the query.  The resp parameter of the callback is
 * only valid if status is 0.
 *
 * If the return value of ib_sa_path_rec_get() is negative, it is an
 * error code.  Otherwise it is a query ID that can be used to cancel
 * the query.
 */
int ib_sa_path_rec_get(struct ib_sa_client *client,
                       struct ib_device *device, u8 port_num,
                       struct ib_sa_path_rec *rec,
                       ib_sa_comp_mask comp_mask,
                       int timeout_ms, gfp_t gfp_mask,
                       void (*callback)(int status,
                                        struct ib_sa_path_rec *resp,
                                        void *context),
                       void *context,
                       struct ib_sa_query **sa_query)
{
        struct ib_sa_path_query *query;
        struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
        struct ib_sa_port   *port;
        struct ib_mad_agent *agent;
        struct ib_sa_mad *mad;
        int ret;

        if (!sa_dev)
                return -ENODEV;

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        agent = port->agent;

        query = kzalloc(sizeof(*query), gfp_mask);
        if (!query)
                return -ENOMEM;

        query->sa_query.port     = port;
        ret = alloc_mad(&query->sa_query, gfp_mask);
        if (ret)
                goto err1;

        ib_sa_client_get(client);
        query->sa_query.client = client;
        query->callback        = callback;
        query->context         = context;

        mad = query->sa_query.mad_buf->mad;
        init_mad(mad, agent);

        query->sa_query.callback = callback ? ib_sa_path_rec_callback : NULL;
        query->sa_query.release  = ib_sa_path_rec_release;
        mad->mad_hdr.method      = IB_MGMT_METHOD_GET;
        mad->mad_hdr.attr_id     = cpu_to_be16(IB_SA_ATTR_PATH_REC);
        mad->sa_hdr.comp_mask    = comp_mask;

        ib_pack(path_rec_table, ARRAY_SIZE(path_rec_table), rec, mad->data);

        *sa_query = &query->sa_query;

        query->sa_query.flags |= IB_SA_ENABLE_LOCAL_SERVICE;
        query->sa_query.mad_buf->context[1] = rec;

        ret = send_mad(&query->sa_query, timeout_ms, gfp_mask);
        if (ret < 0)
                goto err2;

        return ret;

err2:
        *sa_query = NULL;
        ib_sa_client_put(query->sa_query.client);
        free_mad(&query->sa_query);

err1:
        kfree(query);
        return ret;
}
EXPORT_SYMBOL(ib_sa_path_rec_get);

static void ib_sa_service_rec_callback(struct ib_sa_query *sa_query,
                                    int status,
                                    struct ib_sa_mad *mad)
{
        struct ib_sa_service_query *query =
                container_of(sa_query, struct ib_sa_service_query, sa_query);

        if (mad) {
                struct ib_sa_service_rec rec;

                ib_unpack(service_rec_table, ARRAY_SIZE(service_rec_table),
                          mad->data, &rec);
                query->callback(status, &rec, query->context);
        } else
                query->callback(status, NULL, query->context);
}

static void ib_sa_service_rec_release(struct ib_sa_query *sa_query)
{
        kfree(container_of(sa_query, struct ib_sa_service_query, sa_query));
}

/**
 * ib_sa_service_rec_query - Start Service Record operation
 * @client:SA client
 * @device:device to send request on
 * @port_num: port number to send request on
 * @method:SA method - should be get, set, or delete
 * @rec:Service Record to send in request
 * @comp_mask:component mask to send in request
 * @timeout_ms:time to wait for response
 * @gfp_mask:GFP mask to use for internal allocations
 * @callback:function called when request completes, times out or is
 * canceled
 * @context:opaque user context passed to callback
 * @sa_query:request context, used to cancel request
 *
 * Send a Service Record set/get/delete to the SA to register,
 * unregister or query a service record.
 * The callback function will be called when the request completes (or
 * fails); status is 0 for a successful response, -EINTR if the query
 * is canceled, -ETIMEDOUT is the query timed out, or -EIO if an error
 * occurred sending the query.  The resp parameter of the callback is
 * only valid if status is 0.
 *
 * If the return value of ib_sa_service_rec_query() is negative, it is an
 * error code.  Otherwise it is a request ID that can be used to cancel
 * the query.
 */
int ib_sa_service_rec_query(struct ib_sa_client *client,
                            struct ib_device *device, u8 port_num, u8 method,
                            struct ib_sa_service_rec *rec,
                            ib_sa_comp_mask comp_mask,
                            int timeout_ms, gfp_t gfp_mask,
                            void (*callback)(int status,
                                             struct ib_sa_service_rec *resp,
                                             void *context),
                            void *context,
                            struct ib_sa_query **sa_query)
{
        struct ib_sa_service_query *query;
        struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
        struct ib_sa_port   *port;
        struct ib_mad_agent *agent;
        struct ib_sa_mad *mad;
        int ret;

        if (!sa_dev)
                return -ENODEV;

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        agent = port->agent;

        if (method != IB_MGMT_METHOD_GET &&
            method != IB_MGMT_METHOD_SET &&
            method != IB_SA_METHOD_DELETE)
                return -EINVAL;

        query = kzalloc(sizeof(*query), gfp_mask);
        if (!query)
                return -ENOMEM;

        query->sa_query.port     = port;
        ret = alloc_mad(&query->sa_query, gfp_mask);
        if (ret)
                goto err1;

        ib_sa_client_get(client);
        query->sa_query.client = client;
        query->callback        = callback;
        query->context         = context;

        mad = query->sa_query.mad_buf->mad;
        init_mad(mad, agent);

        query->sa_query.callback = callback ? ib_sa_service_rec_callback : NULL;
        query->sa_query.release  = ib_sa_service_rec_release;
        mad->mad_hdr.method      = method;
        mad->mad_hdr.attr_id     = cpu_to_be16(IB_SA_ATTR_SERVICE_REC);
        mad->sa_hdr.comp_mask    = comp_mask;

        ib_pack(service_rec_table, ARRAY_SIZE(service_rec_table),
                rec, mad->data);

        *sa_query = &query->sa_query;

        ret = send_mad(&query->sa_query, timeout_ms, gfp_mask);
        if (ret < 0)
                goto err2;

        return ret;

err2:
        *sa_query = NULL;
        ib_sa_client_put(query->sa_query.client);
        free_mad(&query->sa_query);

err1:
        kfree(query);
        return ret;
}
EXPORT_SYMBOL(ib_sa_service_rec_query);

static void ib_sa_mcmember_rec_callback(struct ib_sa_query *sa_query,
                                        int status,
                                        struct ib_sa_mad *mad)
{
        struct ib_sa_mcmember_query *query =
                container_of(sa_query, struct ib_sa_mcmember_query, sa_query);

        if (mad) {
                struct ib_sa_mcmember_rec rec;

                ib_unpack(mcmember_rec_table, ARRAY_SIZE(mcmember_rec_table),
                          mad->data, &rec);
                query->callback(status, &rec, query->context);
        } else
                query->callback(status, NULL, query->context);
}

static void ib_sa_mcmember_rec_release(struct ib_sa_query *sa_query)
{
        kfree(container_of(sa_query, struct ib_sa_mcmember_query, sa_query));
}

int ib_sa_mcmember_rec_query(struct ib_sa_client *client,
                             struct ib_device *device, u8 port_num,
                             u8 method,
                             struct ib_sa_mcmember_rec *rec,
                             ib_sa_comp_mask comp_mask,
                             int timeout_ms, gfp_t gfp_mask,
                             void (*callback)(int status,
                                              struct ib_sa_mcmember_rec *resp,
                                              void *context),
                             void *context,
                             struct ib_sa_query **sa_query)
{
        struct ib_sa_mcmember_query *query;
        struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
        struct ib_sa_port   *port;
        struct ib_mad_agent *agent;
        struct ib_sa_mad *mad;
        int ret;

        if (!sa_dev)
                return -ENODEV;

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        agent = port->agent;

        query = kzalloc(sizeof(*query), gfp_mask);
        if (!query)
                return -ENOMEM;

        query->sa_query.port     = port;
        ret = alloc_mad(&query->sa_query, gfp_mask);
        if (ret)
                goto err1;

        ib_sa_client_get(client);
        query->sa_query.client = client;
        query->callback        = callback;
        query->context         = context;

        mad = query->sa_query.mad_buf->mad;
        init_mad(mad, agent);

        query->sa_query.callback = callback ? ib_sa_mcmember_rec_callback : NULL;
        query->sa_query.release  = ib_sa_mcmember_rec_release;
        mad->mad_hdr.method      = method;
        mad->mad_hdr.attr_id     = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
        mad->sa_hdr.comp_mask    = comp_mask;

        ib_pack(mcmember_rec_table, ARRAY_SIZE(mcmember_rec_table),
                rec, mad->data);

        *sa_query = &query->sa_query;

        ret = send_mad(&query->sa_query, timeout_ms, gfp_mask);
        if (ret < 0)
                goto err2;

        return ret;

err2:
        *sa_query = NULL;
        ib_sa_client_put(query->sa_query.client);
        free_mad(&query->sa_query);

err1:
        kfree(query);
        return ret;
}

/* Support GuidInfoRecord */
static void ib_sa_guidinfo_rec_callback(struct ib_sa_query *sa_query,
                                        int status,
                                        struct ib_sa_mad *mad)
{
        struct ib_sa_guidinfo_query *query =
                container_of(sa_query, struct ib_sa_guidinfo_query, sa_query);

        if (mad) {
                struct ib_sa_guidinfo_rec rec;

                ib_unpack(guidinfo_rec_table, ARRAY_SIZE(guidinfo_rec_table),
                          mad->data, &rec);
                query->callback(status, &rec, query->context);
        } else
                query->callback(status, NULL, query->context);
}

static void ib_sa_guidinfo_rec_release(struct ib_sa_query *sa_query)
{
        kfree(container_of(sa_query, struct ib_sa_guidinfo_query, sa_query));
}

int ib_sa_guid_info_rec_query(struct ib_sa_client *client,
                              struct ib_device *device, u8 port_num,
                              struct ib_sa_guidinfo_rec *rec,
                              ib_sa_comp_mask comp_mask, u8 method,
                              int timeout_ms, gfp_t gfp_mask,
                              void (*callback)(int status,
                                               struct ib_sa_guidinfo_rec *resp,
                                               void *context),
                              void *context,
                              struct ib_sa_query **sa_query)
{
        struct ib_sa_guidinfo_query *query;
        struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
        struct ib_sa_port *port;
        struct ib_mad_agent *agent;
        struct ib_sa_mad *mad;
        int ret;

        if (!sa_dev)
                return -ENODEV;

        if (method != IB_MGMT_METHOD_GET &&
            method != IB_MGMT_METHOD_SET &&
            method != IB_SA_METHOD_DELETE) {
                return -EINVAL;
        }

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        agent = port->agent;

        query = kzalloc(sizeof(*query), gfp_mask);
        if (!query)
                return -ENOMEM;

        query->sa_query.port = port;
        ret = alloc_mad(&query->sa_query, gfp_mask);
        if (ret)
                goto err1;

        ib_sa_client_get(client);
        query->sa_query.client = client;
        query->callback        = callback;
        query->context         = context;

        mad = query->sa_query.mad_buf->mad;
        init_mad(mad, agent);

        query->sa_query.callback = callback ? ib_sa_guidinfo_rec_callback : NULL;
        query->sa_query.release  = ib_sa_guidinfo_rec_release;

        mad->mad_hdr.method      = method;
        mad->mad_hdr.attr_id     = cpu_to_be16(IB_SA_ATTR_GUID_INFO_REC);
        mad->sa_hdr.comp_mask    = comp_mask;

        ib_pack(guidinfo_rec_table, ARRAY_SIZE(guidinfo_rec_table), rec,
                mad->data);

        *sa_query = &query->sa_query;

        ret = send_mad(&query->sa_query, timeout_ms, gfp_mask);
        if (ret < 0)
                goto err2;

        return ret;

err2:
        *sa_query = NULL;
        ib_sa_client_put(query->sa_query.client);
        free_mad(&query->sa_query);

err1:
        kfree(query);
        return ret;
}
EXPORT_SYMBOL(ib_sa_guid_info_rec_query);

/* Support get SA ClassPortInfo */
static void ib_sa_classport_info_rec_callback(struct ib_sa_query *sa_query,
                                              int status,
                                              struct ib_sa_mad *mad)
{
        unsigned long flags;
        struct ib_sa_classport_info_query *query =
                container_of(sa_query, struct ib_sa_classport_info_query, sa_query);

        if (mad) {
                struct ib_class_port_info rec;

                ib_unpack(classport_info_rec_table,
                          ARRAY_SIZE(classport_info_rec_table),
                          mad->data, &rec);

                spin_lock_irqsave(&sa_query->port->classport_lock, flags);
                if (!status && !sa_query->port->classport_info.valid) {
                        memcpy(&sa_query->port->classport_info.data, &rec,
                               sizeof(sa_query->port->classport_info.data));

                        sa_query->port->classport_info.valid = true;
                }
                spin_unlock_irqrestore(&sa_query->port->classport_lock, flags);

                query->callback(status, &rec, query->context);
        } else {
                query->callback(status, NULL, query->context);
        }
}

static void ib_sa_portclass_info_rec_release(struct ib_sa_query *sa_query)
{
        kfree(container_of(sa_query, struct ib_sa_classport_info_query,
                           sa_query));
}

int ib_sa_classport_info_rec_query(struct ib_sa_client *client,
                                   struct ib_device *device, u8 port_num,
                                   int timeout_ms, gfp_t gfp_mask,
                                   void (*callback)(int status,
                                                    struct ib_class_port_info *resp,
                                                    void *context),
                                   void *context,
                                   struct ib_sa_query **sa_query)
{
        struct ib_sa_classport_info_query *query;
        struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
        struct ib_sa_port *port;
        struct ib_mad_agent *agent;
        struct ib_sa_mad *mad;
        struct ib_class_port_info cached_class_port_info;
        int ret;
        unsigned long flags;

        if (!sa_dev)
                return -ENODEV;

        port  = &sa_dev->port[port_num - sa_dev->start_port];
        agent = port->agent;

        /* Use cached ClassPortInfo attribute if valid instead of sending mad */
        spin_lock_irqsave(&port->classport_lock, flags);
        if (port->classport_info.valid && callback) {
                memcpy(&cached_class_port_info, &port->classport_info.data,
                       sizeof(cached_class_port_info));
                spin_unlock_irqrestore(&port->classport_lock, flags);
                callback(0, &cached_class_port_info, context);
                return 0;
        }
        spin_unlock_irqrestore(&port->classport_lock, flags);

        query = kzalloc(sizeof(*query), gfp_mask);
        if (!query)
                return -ENOMEM;

        query->sa_query.port = port;
        ret = alloc_mad(&query->sa_query, gfp_mask);
        if (ret)
                goto err1;

        ib_sa_client_get(client);
        query->sa_query.client = client;
        query->callback        = callback;
        query->context         = context;

        mad = query->sa_query.mad_buf->mad;
        init_mad(mad, agent);

        query->sa_query.callback = callback ? ib_sa_classport_info_rec_callback : NULL;

        query->sa_query.release  = ib_sa_portclass_info_rec_release;
        /* support GET only */
        mad->mad_hdr.method      = IB_MGMT_METHOD_GET;
        mad->mad_hdr.attr_id     = cpu_to_be16(IB_SA_ATTR_CLASS_PORTINFO);
        mad->sa_hdr.comp_mask    = 0;
        *sa_query = &query->sa_query;

        ret = send_mad(&query->sa_query, timeout_ms, gfp_mask);
        if (ret < 0)
                goto err2;

        return ret;

err2:
        *sa_query = NULL;
        ib_sa_client_put(query->sa_query.client);
        free_mad(&query->sa_query);

err1:
        kfree(query);
        return ret;
}
EXPORT_SYMBOL(ib_sa_classport_info_rec_query);

static void send_handler(struct ib_mad_agent *agent,
                         struct ib_mad_send_wc *mad_send_wc)
{
        struct ib_sa_query *query = mad_send_wc->send_buf->context[0];
        unsigned long flags;

        if (query->callback)
                switch (mad_send_wc->status) {
                case IB_WC_SUCCESS:
                        /* No callback -- already got recv */
                        break;
                case IB_WC_RESP_TIMEOUT_ERR:
                        query->callback(query, -ETIMEDOUT, NULL);
                        break;
                case IB_WC_WR_FLUSH_ERR:
                        query->callback(query, -EINTR, NULL);
                        break;
                default:
                        query->callback(query, -EIO, NULL);
                        break;
                }

        spin_lock_irqsave(&idr_lock, flags);
        idr_remove(&query_idr, query->id);
        spin_unlock_irqrestore(&idr_lock, flags);

        free_mad(query);
        ib_sa_client_put(query->client);
        query->release(query);
}

static void recv_handler(struct ib_mad_agent *mad_agent,
                         struct ib_mad_send_buf *send_buf,
                         struct ib_mad_recv_wc *mad_recv_wc)
{
        struct ib_sa_query *query;

        if (!send_buf)
                return;

        query = send_buf->context[0];
        if (query->callback) {
                if (mad_recv_wc->wc->status == IB_WC_SUCCESS)
                        query->callback(query,
                                        mad_recv_wc->recv_buf.mad->mad_hdr.status ?
                                        -EINVAL : 0,
                                        (struct ib_sa_mad *) mad_recv_wc->recv_buf.mad);
                else
                        query->callback(query, -EIO, NULL);
        }

        ib_free_recv_mad(mad_recv_wc);
}

static void ib_sa_add_one(struct ib_device *device)
{
        struct ib_sa_device *sa_dev;
        int s, e, i;
        int count = 0;

        s = rdma_start_port(device);
        e = rdma_end_port(device);

        sa_dev = kzalloc(sizeof *sa_dev +
                         (e - s + 1) * sizeof (struct ib_sa_port),
                         GFP_KERNEL);
        if (!sa_dev)
                return;

        sa_dev->start_port = s;
        sa_dev->end_port   = e;

        for (i = 0; i <= e - s; ++i) {
                spin_lock_init(&sa_dev->port[i].ah_lock);
                if (!rdma_cap_ib_sa(device, i + 1))
                        continue;

                sa_dev->port[i].sm_ah    = NULL;
                sa_dev->port[i].port_num = i + s;

                spin_lock_init(&sa_dev->port[i].classport_lock);
                sa_dev->port[i].classport_info.valid = false;

                sa_dev->port[i].agent =
                        ib_register_mad_agent(device, i + s, IB_QPT_GSI,
                                              NULL, 0, send_handler,
                                              recv_handler, sa_dev, 0);
                if (IS_ERR(sa_dev->port[i].agent))
                        goto err;

                INIT_WORK(&sa_dev->port[i].update_task, update_sm_ah);

                count++;
        }

        if (!count)
                goto free;

        ib_set_client_data(device, &sa_client, sa_dev);

        /*
         * We register our event handler after everything is set up,
         * and then update our cached info after the event handler is
         * registered to avoid any problems if a port changes state
         * during our initialization.
         */

        INIT_IB_EVENT_HANDLER(&sa_dev->event_handler, device, ib_sa_event);
        if (ib_register_event_handler(&sa_dev->event_handler))
                goto err;

        for (i = 0; i <= e - s; ++i) {
                if (rdma_cap_ib_sa(device, i + 1))
                        update_sm_ah(&sa_dev->port[i].update_task);
        }

        return;

err:
        while (--i >= 0) {
                if (rdma_cap_ib_sa(device, i + 1))
                        ib_unregister_mad_agent(sa_dev->port[i].agent);
        }
free:
        kfree(sa_dev);
        return;
}

static void ib_sa_remove_one(struct ib_device *device, void *client_data)
{
        struct ib_sa_device *sa_dev = client_data;
        int i;

        if (!sa_dev)
                return;

        ib_unregister_event_handler(&sa_dev->event_handler);

        flush_workqueue(ib_wq);

        for (i = 0; i <= sa_dev->end_port - sa_dev->start_port; ++i) {
                if (rdma_cap_ib_sa(device, i + 1)) {
                        ib_unregister_mad_agent(sa_dev->port[i].agent);
                        if (sa_dev->port[i].sm_ah)
                                kref_put(&sa_dev->port[i].sm_ah->ref, free_sm_ah);
                }

        }

        kfree(sa_dev);
}

int ib_sa_init(void)
{
        int ret;

        get_random_bytes(&tid, sizeof tid);

        ret = ib_register_client(&sa_client);
        if (ret) {
                pr_err("Couldn't register ib_sa client\n");
                goto err1;
        }

        ret = mcast_init();
        if (ret) {
                pr_err("Couldn't initialize multicast handling\n");
                goto err2;
        }

        return 0;

err2:
        ib_unregister_client(&sa_client);
err1:
        return ret;
}

void ib_sa_cleanup(void)
{
        mcast_cleanup();
        ib_unregister_client(&sa_client);
        idr_destroy(&query_idr);
}